Card Rulings:Abyssal Designator

• If your opponent sends a monster to the Graveyard with the declared Type and Attribute, you cannot see their hand and Deck. But if they claim to have no such card, you can check their hand and Deck to confirm.

Japanese Rulings

• If the opponent has monsters with the declared typ in both their hand and Deck, they select either their hand or Deck to discard from.